Basic Electronics Fundamentals

BASIC ELECTRONICS

Enabling aMicroelectronic World®

MODULE 1:

© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

What is ELECTRICITY?

It is the flow of electrical charge or power. Itis the invisible force that produces heat, light,motion, and many other physical effects.


To understand the flow of electrical charge, let us firstunderstand the composition of an ATOM. An atom is the smallest, indivisible piece of matter.

nucleus Protons(neutrons are also includedin the nucleus)

Electrons

ATOM© 2005 Amkor Technology, Inc.Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

The First Law of Electrostatics• The negative charge of the electron is equal, but opposite to, the positive charge of the proton.• Unlike charges attract each other, like charges repel.(Coulomb’s Law)

-+ attract

+--+repel

protons

-+© 2005 Amkor Technology, Inc. No. of protons = No. of electrons

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When an external force is applied, electrons located atthe outer shell may likely detached from the atom (due toweaker force of attraction) and may be transferred toanother atom. Free electrons

External force(voltage)

There will be flow of free electrons (electricity)Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

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ELECTRIC CHARGE (Q) The force of attraction or repulsion.

Unit: Coulomb (C)1 C = amount of electric charge carried by acurrent of 1 ampere flowing for 1 second.1 C = 6.24×1018 electrons (or protons)


VOLTAGE (V, E or EMF)

Can be thought of as the force or the “push” that getselectron moving through a conductor.

Unit: Volt (V)


CURRENT (I) It refers to the number of electrons passing a given point in 1 second.

Unit: Ampere (A)1 A = 6.24×1018 electrons pass a certain point in one second.© 2005 Amkor Technology, Inc.Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T


RESISTANCE (R) The opposition to the flow of electrons or current in the circuit.

Unit: Ohm1 ohm of resistance will allow only 1 ampere ofcurrent when the circuit is supplied with 1 volt.© 2005 Amkor Technology, Inc.Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

DC CIRCUIT WATER ANALOGY


VOLTAGE - PRESSURE ANALOGY


GROUND - RESERVOIR ANALOGY


CURRENT - FLOWRATE ANALOGY

A large pipe offers very little resistance to flow

A wire offers very littleresistance to charge flow


RESISTANCE TO FLOW


OHM’S LAW The potential difference (voltage) across an ideal conductor is proportional to the current through it.

V=IxRWhere:V - voltageI - currentR - resistance


POWER (P) The amount of electrical work that voltage and current has exerted in a circuit.

P=VxI Unit: Watt1 watt of power used in 1 second is equivalentto 0.24 calories of heat energy.


Ohm’s Law Pie Chart


EXERCISES



DIRECT CURRENT (DC) Electrical current is flowing in only one direction in a circuit.

Sources: Batteries, DC Power Supply, Solar cells, fuel cells, etc.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

HOW IS DC CURRENT PRODUCED?

While the battery remains unconnected theelectrons on the negative terminal cannotreach the positive terminal.

If the two terminals of the battery are connectedtogether electrons are then able to pass long thewire from the negative terminal to the positiveterminal to attempt to balance the electrical charge.This is a DC current.


ALTERNATING CURRENT (AC) Electrical current flowing in a circuit is constantly being reversed back and forth. This is the type of electricity that we get from plugs in the wall.

Sources: AC Generators, AC outlet


HOW IS AC CURRENT PRODUCED? Electric Generator

As the wire rotates in the magnetic field,the changing strength of the magneticfield through the wire produces a forcewhich drives the electric chargesaround the wire.The faster the loop rotates the largerthe force on the electric charges andthe larger the electric current.


Power plantgenerates electricity

Transmission linecarries electricity long distances Distribution line

carries electricity to house

Transformer steps up voltage for transmission

Neighborhoodtransformer steps down voltage

Transformer on polesteps down voltage before entering house


FREQUENCY (f) Defined as the number of complete cycles that occurs in one second. Unit : Hertz (cycles per second)

1 second


PERIOD (T) The amount of time it takes to complete a single cycle.

T=1/fUnit : secondsPeriod (T)

Period and Frequency are inversely related.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

PEAK TO PEAK VOLTAGE (Vp-p) The peak to peak voltage is the voltage measured from the positive peak to the negative peak value of the signal.


PEAK VOLTAGE (Vp) The peak voltage is the voltage measured from the zero mark to either the positive (+) peak or the negative (-) peak value of the signal.


AVERAGE VOLTAGE (V ave) For AC signal with equal positive and negative alternations, V ave = 0V For AC signal without positive or negative alternations, V ave = 0.318 Vp


RMS VOLTAGE (Vrms) The equivalent DC or the effective value of an AC waveform. Vrms = 0.707 Vp


EXERCISES


MODULE 3:

A device that does not a require source of energy for its operation



RESISTORS They are specifically designed to limit the current. Symbol:

Potentiometer Rheostat

Fixed resistor Variable Resistor


RESISTOR PARAMETERS Resistance Value - refers to the amount of opposition a resistor offers to the flow of current, expressed in ohms. Tolerance - refers to the maximum change in resistance from the nominal or rated value. Power Rating - refers to the continuous power, in watts, that a resistor can dissipate at temperature as high as 70 degrees Celsius. Temperature Coefficient of Resistance (TCR) - indicates how resistance changes with temperature. It is expressed as a percentage change in the nominal value at 25 degrees Celsius for each degree Celsius or in ppm/degree Celsius.


CLASSIFICATION OF RESISTORS A. Fixed Resistors 1. Carbon Composition Fine granulated carbon (graphite) is mixed with clay and hardened. The resistance depends on the proportion of carbon to clay; the higher this ratio, the lower the resistance. Resistance: 1 ohm - 100 Mega ohm Power Ratings: 1/8 to 2 Watts TCR: high (>500ppm/C)


2. Film Type Composed of a resistive material deposited evenly onto a high- grade ceramic rod. The resistive film may be carbon (carbon film), nickel chromium (metal film), a mixture of metals and glass (metal glaze), or metal and insulating oxide (metal oxide).

Carbon film Metal Oxide film

Metal Glaze film© 2005 Amkor Technology, Inc.

Metal film JULY 2005, HR OD-T

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3. Wirewound Type These are made from wrapping resistance wire around a ceramic or other high-insulating cylinder. The assembly is then covered with enamel glaze and baked. They are used in circuits which carry large currents, or in circuits where accurate resistance values are required.


4. Resistor Networks Resistors in various configurations packed in the dual-in-line package (DIP) or single-in-line (SIP) and are used for integrated circuits. DIP typically contains 14 to 16 pins.

SIP Resistor Networks

5. Chip Resistors This type of fixed resistor is in the category of SMT (surface mount technology) component. It has the advantage of a very small size for compact assemblies.


CLASSIFICATION OF RESISTORS B. Variable Resistors 1. Single-turn Potentiometer It is used as gain, treble or bass control in an amplifier and as brightness and contact control in TV receivers.

Resistance:50 ohms and higher Power Rating:Between 2W and 3W


2. Multiple-turn Potentiometer This is used in application that requires precise setting of a resistance value.

3. Trimmer Potentiometer This is used generally for one-time adjustment of resistance. Available for single or multiple-turn units. Resistance: few ohms to 5 Mega ohms Tolerance: +/- 10% Power Rating: 1W© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

RESISTOR COLOUR CODING


LETTER CODING Significant digits

5W 2K2J Tolerance Multiplier Power ratingThe resistor has a value

of 2.2 K ohms, +/- 5%


RESISTOR TEST PROCEDURES A. Fixed Resistors Interpret the color code of the resistor. Measure the resistance of the resistor by connecting an ohmmeter in parallel with the device. Indications Good if within the tolerance range Open resistor if resistance is INFINITE. Out-of-tolerance if resistance is not within the color range value (manufacturer’s defects)© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

RESISTOR TEST PROCEDURES B. Variable Resistor (potentiometer)

ba c ab

c

Ra-b and Rb-c vary as shaft is rotated, potentiometer is in good condition.


GOOD if Ra-c = rated resistanceabc OPEN if Ra-c = infinite

SHORTED if Ra-c = 0 ohms

Caution: Never perform resistance measurements in a live circuit. This will cause damage to an ohmmeter.


CAUSES OF FAILURES A. Fixed Resistors High temperatures High voltages B. Variable Resistors High voltages Accumulation of dirt, moist, foreign substances to resistive elements


RESISTORS IN SERIES

1

I total = I 1 = I 2 = I 3 = … = I nV total = V1 + V2 + V3 + … +VnR total = R1 + R2 + R3 + … +RnP total = P1 + P2 + P3 + … +Pn


RESISTORS IN PARALLEL I total = I 1 + I 2 + I 3 + … + I n V supply = V1 = V2 = V3 = … =Vn 1 1 1 1 1 R total = R1 + R2 + R3 + … +Rn P total = P1 + P2 + P3 + … +Pn


When rules of series and parallel circuits cannot beapplied, more general methods of analysis becomenecessary. KIRCHOFF’S LAWKirchoff’s Current LawThe algebraic sum of the currentsentering and leaving any point ina circuit is equal to zero.


Kirchoff’s Voltage Law The algebraic sum of the voltages around any closed path of the circuit is zero. The sum of the voltage drops will exactly equal the total sum of the voltage rises.


ACTIVITIES


Activity # 1: TESTING A FIXED RESISTORObjectivesUpon completion of this activity, the students must beable to1. Interpret the resistor’s color code.2. Properly use the VOM as an ohmmeter to measure resistance..3. Identify a good resistor by comparing its measured resistance and color code resistance.MaterialsResistor ModuleCalculator (optional)AVOM (Analog Volt-Ohm-Milliammeter)


Activity # 2: USING POTENTIOMETER IN A CIRCUITObjectivesUpon completion of this activity, the students must beable to1. Use the potentiometer as a variable current limiter2. Use the potentiometer as a voltage dividerMaterialsDC Power SupplyVOMPlug-in ModuleConnecting WiresResistors: 1 K Ohm potentiometerLamp: 12 V (1)


Activity # 3: MEASURING VOLTAGE, CURRENT AND RESISTANCE IN A SERIES CIRCUIT Objectives Upon completion of this activity, the students must be able to 1. Measure the voltage, the current, and the total resistance in a series circuit. 2. Evaluate the characteristics of a series circuit. Materials DC Power Supply VOM Plug-in Module Connecting Wires Resistors: 270 ohms, 330 ohms, 470 ohms


Activity # 4: MEASURING VOLTAGE, CURRENT AND RESISTANCE IN A PARALLEL CIRCUITObjectivesUpon completion of this activity, the students must beable to1. Measure the voltage, the current, and the total resistance in a parallel circuit.2. Evaluate the characteristics of a parallel circuit.MaterialsDC Power SupplyVOMPlug-in ModuleConnecting WiresResistors: 270 ohms, 330 ohms, 470 ohms


Activity # 5: MEASURING VOLTAGE AND FREQUENCY USING THE OSCILLOSCOPE Objectives Upon completion of this activity, the students must be able to measure voltage and frequency using the oscilloscope. Materials VOM Oscilloscope Audio Generator Plug-in Module Connecting Wires Resistors: 2.2 K ohms, 3.3 K ohms



CAPACITOR It stores electricity, or electrical energy. Symbol:

capacitor Polarized capacitor

variable capacitor trimmer capacitor


CAPACITOR PARAMETERS Capacitance (C) - refers to the ability of the device to store a certain amount of electric charge. Unit: Farad (F)

Factors affecting the capacitance:1. Plate area - larger plate area increases the capacitance.2. Dielectric thickness - thicker dielectric decreases the capacitance.Working Voltage - maximum voltage that can be impressedacross a capacitor for continuous operation.This rating must indicate whether the voltageis DC or AC.


Ambient Temperature - the variation in capacitance expressed as a percentage of its specified value at 25 degrees Celsius is referred to as nominal value.Temperature Coefficient - the change in capacitance per degree in temperature. It generally expressed in parts per million per degree Celsius.DC Leakage - refers to the minute direct current that flows in a capacitor at a specified direct voltage. Leakage is due to the presence of a few free carriers of charge in the dielectric. For this reason, a charge in a capacitor cannot be stored indefinitely, and it ultimately leaks off.Capacitive Reactance (Xc) - the opposition in ohms, offered by a capacitor to the alternating current.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

CLASSIFICATION OF CAPACITORS A. Fixed Capacitors 1. Mica Capacitors These consists of alternate layers of metal foil and thin sheets of mica. The metal foil forms the plate, with alternate foil sheets connected together to increase plate area. This mica/foil stack is encapsulated in an insulating material such as bakelite-mica. Capacitance: 1 pF to 0.1 microFarad Voltage Ratings: 100 - 2500 Vdc Temp. Coefficients: -20 to +100 ppm/C


2. Ceramic Capacitors These capacitors utilize ceramic dielectric, commonly available in a ceramic disk form in a multi-layer radial-lead configuration. Capacitance: 1 pF to 2.2 microFarad Voltage Ratings: 6 Vdc Temp. Coefficient: 200,000 ppm/C

3. Paper Capacitors Made of flat thin strips of metal foil conductors that are separated by waxed paper (the dielectric material). Capacitance: 300 pF to 4 microFarad Voltage Ratings: up to 600 Vdc

(A) - construction(B) - cardboard-encased capacitor© 2005 Amkor Technology, Inc.Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

4. Electrolytic Capacitors Used where a large amount of capacitance is required.

Capacitance:up to over 200,000 microFarad Voltage Ratings: 350 Vdc maximum DC Leakage: High


CLASSIFICATION OF CAPACITORS B. Variable Capacitors 1. Air Capacitors Variable caps with air dielectric are sometimes used as capacitors in applications requiring frequency selection. These capacitors are constructed of several plates that are meshed together.

Capacitance varies when the shaft is rotated.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

2. Trimmers and Padders This are adjustable capacitance normally have screwdriver adjustments and used for very fine adjustments in a circuit. Ceramic or mica is a common dielectric in these types of capacitors.


CAPACITOR OPERATION Time Constant - the time it takes for the capacitor to charge to approx. 63% of the applied voltage.

Charging Time - the time it takes for the capacitor to charge 100% of the applied voltage.


Time Constant = R x CCharging Time = 5 x time constant Where, R = resistance, ohms C = capacitance, FaradIf supplied by AC source Capacitor will tend the current to lead the voltage by 90 degrees. A capacitor introduces an AC resistance called the capacitive reactance (Xc) and also expressed in ohms.

Where; f = frequency C = capacitance = 3.14156


CAPACITOR TESTING 1. Decode capacitance value. 2. Select proper range of Ohmmeter. Capacitance in microfarad Ohmmeter Setting below 0.01 - 1 x 10K 1 - 50 x 1K 50 - 1000 x 10 1000 - above x1

3. Discharge the capacitor.4. Connect the ohmmeter across the capacitor. Observe proper polarity when capacitor is polarized. 5. Observe needle deflection.

Good Open Shorted Leaky


CAPACITORS IN SERIES

CAPACITORS IN PARALLEL


ACTIVITIES


Activity # 6: TESTING A CAPACITOR USING AN OHMMETERObjectivesUpon completion of this activity, the students must beable to1. Identify a ceramic, mylar, tantalum, and electronic capacitor2. Identify the value capacitor.3. Identify the condition of a capacitor whether good or defective by using an ohmmeter.MaterialsVOMCapacitors: 10 different varieties of capacitors (electrolytic, tantalum, mylar and ceramic).



INDUCTOR A component that stores energy in the form of a magnetic field. It is a coil of wire on a former, and may have a core of air, iron or ferrite. When an electric current flows in the coil, a magnetic flux is produced in the core. Inductors are mainly used in tuned circuits and to block high frequency AC signals (they are sometimes called chokes). They pass DC easily, but block AC signals, this is the opposite of capacitor.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

Symbol: Fixed inductor Variable inductor

Classification according to type of core material:

Air-core inductor Ferrite-core inductor Iron-core inductor

Common Inductors:


NATURE OF INDUCTORS Induce a voltage across itself with any change in current in its windings. Oppose any change in current in its windings. Oppose AC and pass DC signals. Store energy in the form of a magnetic field.


SELF-INDUCTANCE When a length of wire is formed into a coil, it becomes a basic inductor. Current through the coil produces an electromagnetic field. The magnetic lines of force form a strong magnetic field within and around the coil.

N S

Direction of magnetic field is from North to South© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

Facts on Inductance: 1. When there is current through an inductor, an electromagnetic field is established. 2. An increase in current expands the field, and a decrease in current reduces it. 3. A changing current produces a changing electromagnetic field around the inductor (coil). 4. The changing electromagnetic field induces a voltage across the coil in a direction to oppose the change in current.


INDUCTANCE (L) A measure of a coil’s ability to establish an induced voltage as a result of change in its current and that induced voltage is in direction to oppose that change in current. Unit: Henry (H) Where: L = inductance, Henry N = number of turns = permeability A = cross-sectional area l = coil length, m


PHYSICAL CHARACTERISTICS 1. Core Material Coils are wound on either non-magnetic or magnetic materials. Air, wood,copper, plastic and glass are examples of non-magnetic materials. Iron, nickel, steel, cobalt, or alloys are ferromagnetic materials. 2. Permeability Determines how easily a magnetic field can be established. 3. Number of turns The greater the number of turns, the greater will be the inductance.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

4. Cross-sectional area A larger cross-sectional area means the core is larger and there is more room for magnetic flux, means more self-induced voltage (greater L). 5. Length of coil The length of coil is inversely proportional to the inductance. The compactness of the shorter coil provides shorter distances over which magnetic flux must span. As a result, the magnetic field is stronger and more intense. 6. Inductive Reactance XL

The opposition to sinusoidal current in an inductor.


TEST PROCEDURES Using an ohmmeter: 1. If ohmmeter reading is infinite, OPEN COIL.

2. If ohmmeter reading shows the winding resistance, GOOD.


3. If ohmmeter reading is low resistance winding or near zero, SHORTED.


INDUCTORS IN SERIES

INDUCTORS IN PARALLEL



USES OF TRANSFORMER 1. Power Supplies 2. Protection Circuits 3. Impedance Matching

TRANSFORMER RATINGS 1. Primary Voltage = 220-240V 2. Secondary Voltage = 12V,12-0-12,15-12-9, 6-3-0 V 3. Current Capacity (Icap) = 5A


HOW TRANSFORMER WORKS The function of a transformer is to transfer current, voltage and power from one series of windings (coil) to another.

The two series of windings are linked magnetically.


TRANSFORMER CONSTRUCTION Transformer are basically made up of from two coils which are wound over a common core material formed into a closed magnetic circuit.

PrimaryWinding

Secondary Winding

Types of core: Air, Iron and Ferrite


TURNS RATIO The ratio of the number of turns in the secondary winding (Ns) to the number of turns in the primary winding (Np). = s p

This can also be expressed in terms of voltageand current. = Vs Vp =

IpIs


PRIMARY POWER EQUALS SECONDARY POWER For an ideal transformer, the power in the secondary equals the power in the primary. When the losses are considered, the secondary power is always less. Ps = Pp


CLASSIFICATION OF TRANSFORMERS

Air-core Iron-core Ferrite-core

Air-core and ferrite-core transformer generallyare used for high-frequency applications. Iron-coretransformer are used for audio frequency (AF) andpower applications.


TYPES OF TRANSFORMERS 1. Step-Up Transformer Np < Ns Rp < Rs Ip > Is Vp < Vs 2. Step-Down Transformer Np > Ns Rp > Rs Ip < Is Vp > Vs© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

3. Isolation Transformer Np = Ns Rp = Rs Ip = Is Vp = Vs

Other types of transformers1. Tapped transformer2. Multiple-winding transformer3. Autotransformer


DEFECTS OF TRANSFORMERS 1. Open Primary or Secondary Winding Infinite , no deflection

2. Shorted Primary or Secondary Winding 0 ohm

3. Grounded Primary or Secondary Winding Any amount of deflection



INTRODUCTION TO SEMICONDUCTORCONDUCTOR• Substance, body or material, which has more electronsthat are free to move• Has very low electrical resistance• Allows electric current to flow with easeExample: Metals such as silver, copper, gold, electrolytes, and ionized gases


INSULATOR • Substance, body or material that has a characteristics that is extremely opposite of that of a conductor. • With more than four valence electrons but ideally, it has 8 valence electrons. Example: Rubber, glass, paper, etc.


SEMICONDUCTOR • Substance, body or material that has a characteristic in between a conductor and an insulator. • With 4 valence electron. Example: 1. Elementary semiconductors a. Silicon (Si) b. Germanium (Ge) 2. Compound semiconductors a. Gallium Arsenide (GaAs) b. Aluminum Arsenide (AlAs) c. Gallium Phosphide (GaP)© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

TYPES OF IMPURITIES 1. Pentavalent Impurities • Atoms with 5 valence electrons such as antimony (Sb), arsenic (As), and Phosphorus (P) • They are called DONOR ATOMS. 2. Trivalent Impurities • Atoms with 3 valence electrons such as boron (B), gallium (Ga), and indium (In) • They are called ACCEPTOR ATOMS.


CLASSIFICATION OF SEMICONDUCTORS 1. INTRINSIC SEMICONDUCTOR • It is a pure semiconductor • Every atom in the crystal is a silicon atom


• To make silicon conducting, producers combine or “dope” pure silicon with very small amount of elements like Boron or Phosphorus.

Silicon doped withPhosphorous


2. EXTRINSIC SEMICONDUCTOR • A doped semiconductor • Result of adding an impurity atom to an intrinsic crystal to alter / increase its electrical conductivity Extrinsic semiconductor can be: a. N-type - produced when pentavalent atoms are added to the molten silicon, producing an excess of electrons. Majority carriers: Minority carriers: electrons holes


b. P-type - produced when trivalent atoms are added to the molten silicon, produces an excess of holes.

Majority carriers:Minority carriers:

holeselectrons

Silicon doped with Boron



DIODE A semiconductor device that let current flow only in one direction. Symbol: Cathode (K) Anode (A)

An ideal diode is like a switch. When the switch isclosed, the circuit is completed.


DIODE OPERATION 1. Forward Bias

2. Reverse Bias


DIODE RATINGS 1. Peak Inverse Voltage (PIV) This is the maximum reverse voltage that can be applied to the diode. Exceeding this voltage will break down, conduct and destroy the diode. 2. Forward Voltage (Vf) For silicon diode, Vf = 0.7V For germanium diode, Vf = 0.3V


DIODE TESTING 1. GOOD CONDITION

2. DEFECTIVE CONDITION A. Open Diode – when both combinations indicate high resistance B. Shorted Diode – when both combination indicate zero resistance



BLOCK DIAGRAM

AC SOURCE RECTIFIERFILTERCIRCUIT REGULATOR LOAD

1. AC SOURCE – a section where the input ac signal is applied and converted down to a much lower value, typically a step- down transformer is used.1. RECTIFIER – a section that converts ac signal to pulsating dc.


3. FILTER CIRCUIT A section that removes the unwanted ac signal in a pulsating dc signal, basically consists of capacitor and inductor.4. REGULATOR A section that provides a constant voltage to the load regardless of the input fluctuations.5. LOAD Last section of the dc power supply where the output dc signal is taken.


RECTIFIER CIRCUITS 1. Half-wave Rectifier This type of rectifier employs a single diode that conducts only in one direction.


2. Full-wave Rectifier a. Center-tapped full-wave rectifier


b. Bridge-type full-wave rectifier


FILTER CIRCUITS

RIPPLE – refers to the variation in the output voltage due to the charging and discharging of capacitor.


REGULATOR A circuit for maintaining an essentially constant output voltage under varying input condition or changing the load condition. Vdc 0

0 Unregulated dc voltage

Regulator

Regulated dc voltage

A device that can perform the function of a regulatoris the zener diode.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

SPECIAL DIODESZENER DIODE A diode designed to conduct current when reversed biased with a specific threshold voltage.

Application:1. DC voltage regulators in power supply2. Clipper circuits


LIGHT EMITTING DIODE (LED) A semiconductor device that generates light when sufficiently forward biased.

Application:1. Indicator lamps and readout displays2. Seven-segment display3. Optical coupling application often in conjunction with fiber optics.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

PHOTODIODE Acts as a current generator in which the current is directly proportional to the intensity of light.

Application:1. Automation applications particularly as sensors


VARACTOR Acts like a variable capacitor. A reversed-biased PN junction that utilizes the inherent capacitance of the depletion layer.

Applications:1. Tuning circuits2. FM modulators3. Oscillators4. Bandpass filters5. Automatic frequency control© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

SCHOTTKY DIODE A semiconductor diode formed by attaching a metal conductor to a heavily-doped N-type semiconductor material in order to have faster rectification.

Applications:1. High frequency rectifiers2. Radar systems3. Schottky TTL logic for computers4. Mixers and detectors in communication equipment© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

ACTIVITIES


Activity # 7: TESTING A SILICON DIODEObjectivesUpon completion of this activity, the students must beable to1. Identify the anode and cathode terminals of a diode using an ohmmeter.2. Determine the knee voltage of the silicon diode by its dynamic operation.3. Determine the effect of forward and reverse bias voltage on the diode’s conduction.MaterialsDC Power SupplyVoltmeterPlug-in Module Connecting wires Diode: 1- !N4001 Lamp: 1- 12V


Activity # 8: USING THE DIODE AS A RECTIFIERObjectivesUpon completion of this activity, the students must beable to1. Draw the output waveform of a half-wave and full wave rectifier.2. Measure the average (or DC) output of a half-wave and full-wave rectifier.MaterialsVOMConnecting wiresOscilloscopePlug-in ModuleDiode: 4- !N4001Resistor: 1 K ohm 0.5W (1)Transformer (6V secondary)© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T


TRANSISTORS A three-terminal semiconductor device that is capable of current and voltage amplification, or gain, in conjunction with other circuit elements. The basic principle of transistor operation is that the voltage across two of its terminals controls the current flow in the third terminal.


BIPOLAR JUNCTION TRANSISTOR A. NPN-type B. PNP-type


TRANSISTOR OUTLINES AND PACKAGES


TRANSISTOR TESTING A. Identification of the BASE TERMINAL and the type of transistor.

1. Set the Ohmmeter to R x 1 range. This range can be adjusted up to R x 1K only whenever necessary to increase the meter deflection.2. Connect the Ohmmeter probes to the transistor terminals and look for two pairs of terminals that will provide low-resistance readings. Only these two pairs of terminals, the common terminal is the base.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

3. If during the low resistance reading, the positive probe is connected to the base, then the transistor is NPN type. If during the low resistance reading, the negative probe is connected to the base, then the transistor is PNP type.


B. Identification of the EMITTER and COLLECTOR terminals of the transistor.

1. After knowing the location of the base terminal of the transistor, connect the meter probes to the two unknown terminals.2. Touch the base terminal (or in some cases all the terminals maintaining that no terminals will come in contact with each other).3. Observe the meter deflection. The Ohmmeter should provide a low-resistance reading indicating that the transistor has turned ON.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

4. If the transistor is an NPN type, the terminal where the N (negative) probe is connected is the emitter terminal. The remaining terminal is the collector. If the transistor is PNP type, the terminal where the P (positive) probe is connected is the emitter terminal. The remaining terminal is the collector.


INDICATIONS 1. GOOD INDICATIONS Four pairs should indicate high resistance. Two pairs should indicate low resistance. FB base-emitter junction = low R RB base-emitter junction = high R FB base-collector junction = low R RB base-collector junction = high R collector-emitter (vice versa) = high R 2. DEFECTIVE INDICATION When indications above were not met.© 2005 Amkor Technology, Inc. Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

ACTIVITY


Activity # 9: IDENTIFICATION OF TRANSISTOR TERMINALSObjectivesUpon completion of this activity, the students must beable to1. Identify the emitter, base and collector terminals of the different packages of transistors2. Identify whether the transistor is PNP or NPN type.MaterialsAnalog OhmmeterTransistor: 5 transistor varieties of different packages



AMPLIFIER Circuits that are capable of producing a larger signal using a smaller signal as a pattern. Amplifiers may be classified according to frequency range, methods of inter-stage coupling used, bias point at which the active device operates, voltage, current and power.


CLASSIFICATION OF AMPLIFIER 1. Common Emitter Amplifier • The input signal is applied at the base terminal • The output signal is taken from the collector terminal. • Exhibits high voltage gain (Av), high current gain (Ai), and very high power gain (Ap)


2. Common Collector Amplifier • The input signal is applied at the base terminal • The output signal is taken from the emitter terminal. • Exhibits unity Av. • Output signal is in phase with the input signal.


3. Common Base Amplifier • Input signal is applied at the emitter terminal • Output signal is taken from the collector terminal. • Exhibits unity Ai. • Output signal is in phase with the input signal.


ACTIVITY


Activity # 10: USING THE TRANSISTOR IN A COMMON-EMITTER AMPLIFIERObjectivesUpon completion of this activity, the students must beable to1. Measure the DC bias voltage of a common-emitter amplifier2. Calculate the voltage gain and examine the input-output waveform relationships in a common-emitter amplifier.MaterialsVOMDC Power SupplyAudio GeneratorPlug-in ModuleConnecting Wires Oscilloscope Transistor: 2N3904 or equivalent Resistors: 18K Ohms, 3.9 K Ohms, 1.2 K Ohms 330 Ohms Capacitors: 3.3 microFarad, 16V (2) 22 microFarad, 16V (1) Amkor Confidential / Proprietary Business Information JULY 2005, HR OD-T

© 2005 Amkor Technology, Inc.

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Basic Electronics Fundamentals